Chinese medicinal herb that looks and grows like a tall grass but isnít. It spreads by underground rhizome like grasses, but unlike grasses it has fragrant yellow-white or light purple flowers that open in the evening in late summer and autumn. Used in China for 2000 years. The rhizomes are noted for their antidiabetic and antibacterial properties, and are used for pneumonia, bronchitis, high fever, irritability and insomnia.